#1 - July 9, 2010, 3:38 a.m.
Mail with gold or items from other players take an hour to be delivered, though it sounds like you may be on a trial account, Divinusira.
Trial account have some restrictions in that they are unable to use the mail or auction house system or public channels. More information on trial accounts can be found in the following support article.
http://us.blizzard.com/support/article.xml?locale=en_US&articleId=20590
Those restrictions will lift when you upgrade your account to the standard edition. Please note that if you use the online upgrade feature trial restrictions may take up to 72 hours to be removed. Though leveling restrictions will be lifted immediately the other restrictions remain until your purchase is fully processed.
I hope that clears things up, Divinusira, and welcome to Azeorth! I hope you have a great time here. :)